<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="../jquery/jquery.min.js"></script>
</head>
<body>
    <div id="mydiv">
        <ul>
            <li class="target">1</li>
            <li>2</li>
            <li>3</li>
        </ul>
    </div>
    <div>
        <ul>
            <li><a href="#" class="target">百度</a></li>
            <li><a href="#">博客园</a></li>
        </ul>
    </div>

    <script>
        //设置所有的li前没有小圆点
        $(function(){
            $('li').css('listStyle','none');
            //给id为mydiv层设置宽300px，高150px，边框红色细
            $('#mydiv').css('width','300px')
                       .css('height','150px')
                       .css('border','1px solid red');
            //给类名为target的元素设置前景颜色为绿色
            $('.target').css('color','green');
            //给id为mydiv的元素li设置字体大小为26px
            $('#mydiv li').css('fontSize','26px');
        })
    </script>
</body>
</html>